(CBS) — Stuntman Nik Wallenda braved cool temperatures and 15 mph winds as he walked 50 stories above the streets of Chicago as thousands looked on Sunday evening.

Wallenda walked a tight rope on a 19 degree incline between Marina City’s west tower and the Leo Burnett Building, a 454 foot walk over 600 feet above the Chicago River. The wire was originally supposed to be calibrated to 15 degrees.

The start of the walk was delayed until after 7:30 p.m. but once Wallenda got started, he moved quickly, taking only about 7 minutes to make it across to the Leo Burnett Building.

For the second part of his act, Wallenda returned to Marina City and walked just under a hundred feet between the West and East towers while wearing a blindfold.

Nik Wallenda, a seventh generation member of the Flying Wallendas, walked without the benefit of a safety net. The walk is the highest and steepest high-wire walk in the history of the Flying Wallenda family.

In 2012, Wallenda walked on a tightrope over a stretch of Niagara Falls in 2013 he walked over the Grand Canyon.

The walk was broadcast live on the Discovery Channel and viewing stands were set up on Wacker Drive from Clark to Dearborn and from Wabash to State.